Photoelectric musical system



Filed March 15, 1934 6 Sheets-Sheet l Feb. 25, 1936.

LEREMEEFF PHOTO ELECTRIC MUSICAL SYSTEM Filed March 15, 1934 6Sheets-Sheet 2 lllllllnillll r. I: lilllliliii. Ll.

Iii i l iiffifii MR? IFIIG. 5

INVENTOR. v

111111 "H l mu llnlill m Feb. 25, 1936. EREMEEFF j 2,031,764

PHOTOELECTRIC MUSICAL SYSTEM Filed March 15, 1954 6 Sheets-Sheet 4 11110}. m IFIIGQ 1111 TFJIG. 1411 INVEN TOR.

Feb. '25, 1936.

l. EREME EFF PP-IOTOELECTRIQ MUSICAL: SYSTEM Fii.e d March: 15, 1954 6Sheds-Sheet 15 INVENTOR;

Feb. 25, 1936. l. EREMEEFF 2,031,764 I PHOTOELECTRIC MUSICAL SYSTEMFiled March 15, 1934 6- Sheets-Sheet 6 INVENT OR.

electrical circuits are Patented Feb. 25, 1936 UNITED STATES PATENTOFFICE 2,031,764 rno'roamc'raro MUSICAL SYSTEM Ivan Eremeefl,Philadelphia, Pa. Application- March 15, 1934, Serial No. 715,656

27 Claims.

My present invention relates toa complete electronic musical systemwhich embraces a novel art of preparation of records, wave synthesis,and sound reproduction. An object of my invention is to devise anelectronic musical instrument whose major musical efiects resemble .thekeying touches of a piano and an organ, such instrument being separateor in combination with a sound reproducer.

Another, object'of my invention is to provide as an important part ofthis system, the novel processes of preparation, recording, andreproducing of photographic sound wave patterns.

It is a further object of my invention to provide an electronic musicalinstrument which employs a pitch film and a quality film. The pitch filmis made as a running belt which is endless as the result of accurate andprecise splicing. Provision is also made for the adaptation, if desired,of a slitted revolving drum, in lieu of the fllm, or a multi-planedrevolving scanning mirror. This musical system is provided withprecaution against rubbing or wearing of the films used for pitch andfor quality, by.means of rollers which are so designed that the fihnruns over padded surfaces. The quality film is stationary exceptingduring intervals when it is adjusted to desired positions, eithermanually or by motorized drive. The quality waves are focused on runningscanning pitch slits, instead of. the pitch slits being focused on thequality waves as in motion picture scanning. V This electrical musicalinstrument provides a motorized unit for each keyboard, novel speedcontrolled tremolo and volume control means which do not interfere withthe tone quality, and a diminishing apparatus for sustaining tones,which also permits the production of staccato effects. The instrumentutilizes a variable intensity light source for distribution 01 the lightintensitiesaccording to waves of different frequencies. No used in theactual sound work, excepting in parts such as the amplification, thephotoelectric cell connection; lighting,

etc.

The instrument is provided with novel and emcient light shutters, whichovercome area loss,

such shutters having packing which is provided a i or the purpose ofclosing out undesirable escaping light, said shutters also having novelflexible keying connections. The keys are made of hollow stamping metalor die casting, instead of the conventional wood as in organs andpianos. Since most of the instrument is constructed of metal, I

find it advantageous to have metal keys, also ,1 trackrepresenting acomplete quality,

due to higher efficiency and greater accuracy. The instrument employssynchronous brushless induction motors near its sensitive circuits, anda novel quality film winding device is provided with graduated degreemarkings for the indication of 5 each quality section.

Another object of my present invention is to provide a meter forindicating the sound intensity, which is also applicable forrecordingany other measured values for which a galvanometer is used. 1

A further object of the invention is to devise a sound reproducingdevice, in which a quality film is continually running from one rollerto another. Said film carries a plurality of individual tracks ofrecording, which are made simultaneously, each which is selected by itsown co-operative key in a keyboard, at a predetermined pitch. Light isfocussed on all tracks by means of a single lens. The reproducer employsits own volume control, tremolo control, and diminishing apparatus forcreating different expressional effects. For the sake of compactness ofconstruction, conventional typewriter keys may be utilized. A singlefilament lamp is which has moderate intensity, and is guarded by aplurality of light shutters. Said light source passes light into aspecially corrected objective projection lens which is adapted formulti-tracks, picking up the image from a flat field and focusing it ona flat field without distortion at the edges or in the center.

It is a still further object of my invention to provide a novel processfor the preparation of records, by which lines representing pitch slitsor quality waves are drawn on mathematically ruled graph papers, whichare photographed by novel photographing methods onto films or drums. Inthe preparation of pitch and quality wave. patterns, this systemembraces full wave modulation, additional synthesis of harmonics by oneand two side modulation, spreading modulation, and, methods ofsimplification of fixed wave forms at difierent frequencies, to ensureclear and efiicient recording. The novel two-side recording is providedfor the purpose of enlarging narrow angles for more accuratephotography. This system also includes novel methods of preparing asingle wave form pattern which produces several tones simultaneouslyfrom one key.

It is another object to show a number of diagrammatic assemblies of myinvention, with commercial design, also illustrating the final assemblyinto a cabinet.

Other objects used as a light source,

and advantages in detail of con- I6 is provided with struction andoperation will be apparent as the description proceeds, reference beinghad to the accompanying drawings, in which:

Fig. 1 is a. view of an electronic musical system.

Fig. 2 represents a sound on film apparatus which is an additional partof what is shown in Fig. 1.

Fig. 3 depicts a modification of the system shown in Fig. 1.

Figs. 4 and 5 represent quality and pitch films, respectively, as usedin my musical system.

Fig. 6 is a view of diminishing and keying means.

Fig. 7 and Fig. 7' are detail views of what is shown in Fig. 6.

Figs. 8 and 9 illustrate methods for preparing records such as shown inFigs. 5 and 4.

Figs. 10 to 18, inclusive, represent diagrams illustrating modulatingmethods.

Fig. 19 represents the preparation of a sound pattern by the synthesisof harmonics.

Figs. 20, 21, and 22 depict sound waves representing different tonequalities, with their simplification for recording at differentpredetermined frequencies of a musical scale.

Fig. 23 represents a. commercial unit assembly of what is shown inFig. 1. V

Fig. 24 represents a general complete assembly view of my musicalsystem.

Figs. 25, 26, and 27 represent diagrammatically the wiring and sounddistribution of my invention.

Referring to Fig. 1, I represents a pitch film which rides on severalrollers such as 2, and the tension roller 3, by aid of the motor 4,which has governor 4" and speed control 4". rollers are padded to avoidrubbing and wearing, and are connected by gearing so that the a part ofsake of simplicity. I

The aperture shield 5 permits of focusing prelmages are equally as sharpThe variable translucency disc 8 interrupts light passing from lens I atpredetermined speeds which are controlled by the pedal 9 for theproduction of tremolo effects without interfering with the tone qualityof the output. The variable translucency disc I0 is controlled by pedalIII for regulating volume without interfering with the tone quality. Bydepression of the keys in the keyboard II, predetermined amounts oflight are permitted to pass through the pitch film I onto thephoto-sensitive element I Z'for conversion into electrical energy whichis later amplified and issued as sound energy.

The screw I I shown below the keyboard represents the adjusting meansprovided for each key, to determine the amount of its drop, thuscontrolling the amount of light passing through the space left as aresult of lifting its co-operative light shutter. The quality film'fi isadvanced and retarded to predetermined positions at desired intervals bythe manual winding of crank I3 which is geared with the shaft of rollerI4 in its pulled position, and engaged with shaft I5 in itspushed'position, while, with theaid of a chain, it is engaged withroller I 6.' The shaft of roller an indicator IB' which has which is asingle filament type pointing out the quality section selected. Lightsources I8 consist of a plurality of lamps which are distributed in sucha manner that those frequencies which require greater intensity areprovided with lamps of lighter voltage. I9 is a motorized diminishingand keying means which is controlled in speed by a slipping clutch whichforms a part of the pedal action 20 for speed variation, for longer andshorter time of tone diminishing for producing sustained and fading outtones after the keys of keyboard I I have been released by the Thisdiminishing and keying means is shown in detail in Figs. 6 and '7.

Whe n a predetermined key is depressed, its co-operative light shutteris raised to permit light from It to fall on a predeterminedly set wavetrack on film 6. Said track is illuminated, and its image is focused bylens 'I on the cooperative pitch track of which scans the focused andreduced image. The motors used in t tive circuits are brushless, beingof an induction type, to avoid any parasitic noises. The large size ofthe quality film 6 permits the passage of greater amounts of light,which is not intense enough to warp or fire the film. By the use of thelarge quality film, large light shutters are also employed, and thequality tracks also have comparatively large dimensions. The methods offilm splicing which I use in this system will be described later in thespecification, with regard to Fig. 5.

Fig. 2 represents an additional sound on film apparatus which iscontrolled by the keys of the keyboard 2I, which areillustrated asconventional typewriter keys, for the sake of compactness ofconstruction. The dot and dash lines on the keyboard 2I referto acontinuance of the keys shown, which are too numerous to illustrate. IHowever, the regular keyboard such as II in Fig. 1 may be used in lieuof the type- Writer keys. Each key has connection to its coshutter bymeans of the diminishing device I9. Light from the source I8, lamp, isfocused by the corrected'objective lens 'I through the shield 5 onto therunning quality film 22. Said film is driven by the step pulley 23 fromthe motorized gear drive 24 at predetermined speeds.

graduated degrees for any predetermined speed. By raising any of theshutters by the keyboard 2|, the image of the filament is focused in theform of P light slit onto predetermined periodic and non-periodic wavetracks of the quality film 22.

Said film allows light to pass through its wave tracks in a shutteraction manner to the photo sensitive element I2 for conversion intoelectrithe running pitch film I, v

s system near the sensical and sound energy. The pedals I0 and 9 areprovided for controllin said light in order to produce such efiects astremolo and volume control, as described with reference to Fig. 1. soundon film system shown in Fig. 2 is an addition to the musical systemdescribed above with regard to Fig. 1. With the sound on-film system, amusician or other operator, utilizes the already recorded music orspeech at predetermined pitches, controlled by himself. A musician, forexample, mixes such music with his own musical rendition produced on themusical system as shown in Fig. 1 by playing one keyboard as I! in Fig.l, with one hand, and playing with another hand on keyboard 2 i, as inFig. 2. I

Fig. 3 is a modification of what is shown in Fig. 1, without the movingfilm I, which is shown in Fig. I. Instead, the scanning is made by meansof the multi-planed rotary mirror 15 and its drive 4", which reflectsthe image of the filament of the light source-i8 when any of theshutters are raised by their co-operative keys. The objective lens 1projects said light image onto predetermined wave tracks of thestationary quality film 6 by one-directional scanning. The image of thefilament'of lamp l8 ismade to move in a scanning manner over thestationary quality waves in such a way that when said light imagecommences to scan the beginning of a wave, the

scanning of the end of the preceding wave has already ceased.This'system is provided with intense concentrated light which s'cans oneor more wave lengths at one time, while in Fig. 1, a' plurality ofmoderate intensity light slits compoundly and simultaneously scan aplurality of quality waves, as explained in my co-p'ending patentapplications, Serial Number 686,361, filed 'August 23, 1933, and SerialNumber 697,458, filed November 10, 1933.

The modified film shifting device l3 shows a pair of clutches as 26 and21, which engage one at one time forforward and reverse movement of thefilm 6 on suitable rollers. Each roller hasv friction such as '28.

In order to indicate and measure accurately and represent numerically bya counter the volume of the light energy used in sound production fromeach key, or for any other measuiements which I may wish to make in thefuture,

'I provide my system with a novel meter for this purpose. The output ofthe photosensitive element i2 actuatesthe galvanometer 32proportionally, so that the greater the output of said photosensitiveelement, the greater is the deflection of the galvanometer mirror 29 ondisc 30. Constant light energy asfrom the light source I8 is focused andreflected onto the galvanometer mirror 29 by means of the objective lens29' to the transparent or opaque perforated rotary sur= face 30, whichis coupled to the revolving mirror drive 4' with the aid of a chain 30".In the case of employing an opaque rotary surface, it containsaplurality of rows of perforations as 30" representing differentfrequencies, while if a transparent rotary surface is used. it containsa plurality of rows of opaque wave tracks as 30' which representdifferent frequencies..-.; Thus, signals are produced for drivingasuitable registering device, such as a counter 8G, when the light beamfrom source l8 passes with the aid of shutter ll, through the tracks ofthe surface on the photo ,sensitiveelement l2 when galvanometer 82 isdeflected by current from the circuit-from the amplifier '32" which isfed by line I!" from'the photo sensitive element I! as a result of theimpression of light energies passing from the actuation of predeterminedkeys of the keyboard ll. This-meter is frequency operated', bywhich thegalvanometer movements of measured quantities are multiplied by a fightbeam. Said light beam is interrupted by a socalled light chopper atdifferent frequencies, provided for. each angular deflection of thelight beam in order to impress pulsating light energy on the photosensitive element. with the aid of the amplifier 33, said photosensitive element 'track' which it guards.

, crank 42.

tion. The quality tracks as in the film 8 of Fig. 4,

are enlarged proportionally in wave lengths to correspond to the pitchfilm as shown in Fig. 5.

For example, if the lowest frequency is 32 cycles per second and thepitch slits are fiz inch apart at the'track 31, then the quality trackis enlarged, for example, by four times, making a wave length of twoinches in the wave track 38 of the quality film. Of course, the width ofthe quality wave track is also expanded accordingly. For example, if thewidth of the pitch track at 31 is .100", then the width of the qualitytrack 38 is .400". The width of the individual pitch slits of the pitchfilm are any suitable dimension. However, the

finer the slit is, the finer is the scanning of the I quality wave,provided, of course, that the intensity of the light passing through itpermits.

The pitch film shown in Fig. is spliced at the portion 11, 6, 0, d inthe following manner;- the photographic emulsion from one end of thefilm is taken ofi without scratching, exactly on the line of, forexample, 0, d, which is placed under the other end of the film at lineit, 1). Transparent film cement is used and the accurate matching of thetracks is made under magnification. The film then does not have anycause. for producing an additional distorting sound as it moves. Since.the distance of the splice is only about V8 inch, and also as the filmruns for example, eighty feet per minute, the

shown in Fig. l is depressed in the direction indicated by arrow, theshutter 40 is lifted for example, one inch, opening a slit between theremaining shutters, through which the light from the source l8 falls onthe quality film 6, shown in Fig. 1, passing into the previouslydescribed lens which focuses light on the running pitch film which alsohas been explained. As the finger leaves key 39, the shutter 40 drops byits own weight and closes the small section of the quality This, 'ofcourse, gives an organ action, in which the sound production ceases asthe finger leaves the key, provided that the diminisher spring such as4| is loosened by Said crank movesframe 43 with the aid of the eccentriccams as 44 and 45'. If crank I2 is set to its position for diminishingby stretching the springs as H, the lifted shutter'lll will not fall toa resting position when the finger lifts from the key 39, but will bebrought down at a predetermined rate of speed of. the motor which isgeared to rollers 46 and 41. When all the shut-' ters are brought downto the stop 48, the rollers 48 and 41 are continuously rollingand theshutters are sliding easily. The rollers 48 and 41 roll continuously sothatat any time the diminishing device can be put into operation.staccato effects are produced by the key being hammered by the hand, thekey-respondingas quickly as the movements of the hand.

In Fig. I, a depicts v the shutters as 40. with their spacers ll whichare parts of the roller 48. The

fiexible padding 50 closes out the light escaping through the gapsbetween the shutters. The padded shutter is shown in the detail b ofFig. 7'.

Fig. 8 illustrates a method for the preparation of apitch film.Mathematically calculated distances for each cycle and each frequencyare prepared and rows of very fine lines are drawn or printed onnon-shrinking flexible transparent or opaque material. The distancesbetween the tracks are made, for example, one inch for the low frequencyof C1. In C2 the distance will be inch. In C4 the distance will be $4;inch, and so forth. The distance of C#1 will be only a trifie less thanthat of Cl, which is inversely proportional to the difference betweenthe notes C and C# of a musical scale. That is to say, as the frequencygoes higher, the space becomes smaller.

film, is represented by 6 The surface of said material is, as I havementioned, ruled with lines. These are predeterminedly drawn over inorder to produce a record with slits of predetermined or desired size.

In Fig. 8 the opaque surface is shown placed over a suitable rotarydrum, with edges cemented, and represents a plurality of slits whichhave been drawn on said surface. When the drum is revolved, the slitsare photographed by 52 onto the film 53 which rolls over the drum 54 insuch a manner that when drum 54 revolves once, the

slit drum also makes one revolution, due to the gear drive 55. Anylength of the film as 53 can be utilized. Said film is positive whendeveloped,

as shown by I in Fig. 1. For substituting'film I. Fig; 9 shows thematerial placed on a drum as in Fig. 8, with mathematically calculateddistances. But, in lieu of slits, quality waves are drawn, such as 56,and the drum is brought closer to the lens to be photographed in largesize on the film 51 which is then printed. Such a in Figs. 1, 3, and 4.Figs. 10 to 18, inclusive, show wave patterns which are drawn on opaquesurfaces with mathematically calculated dimensions for each frequency.As I have mentioned, the low frequency C1 has, for example, one inchspace, and Fig. 10 shows a wave pattern drawn in that space inrepetition. However, for high frequencies, as in the seventh octave, foronly a space of l/64 inch, it is impossible to draw any pattern but astraight line, as shown As the frequencies go higher, the original waveform. must be modified in order to example, which affords providesharper registration by the scanning slit which is sometimes only 1/64inch in width.

In Fig. 10 there is shown a pattern which is used for pproximately thefirst to the fourth octaves, and only several steps are available forproducing variation of light by the scanning slit. In Fig. 11 the waverepresents only the highest octave, in which the black and white linesare nearly equal to the width of the scanning slit in the pitch film. Inorder to produce any quality in the high frequencies, I modulate thetops of the lines by a predetermined additional harmonic whose amplitudeis, at thehighest, about 10% of the entire width of the track.

Fig. 11 represents a track of for example, a 4000 cycle tone withmodulation-as 58, which is in the form of a harmonic of 500 cycles,which is combined with the 4000 cycle wave for the purpose of obtainingquality, which is in accordance with the synthesis disclosed in mypatent of August 29, 1933,'Number 1,924,713. I

The wave shown in Fig. 12 resembles that of Fig. 11, but the synthesisof, for example, ,a 4000 cycle tone with a 500 cycle tone 5!, isaccomrect synthesis plished by narrowing and spreading the white lines,increasing 5% and decreasing 5%, totaling 10% modulation.

In Fig. 10 the low frequency permits of placing steps in each wavelength. Additional diis also made by cutting down the tops of thepattern for adding extra harmonics.

Fig. 13 shows a pattern which is modulated in Fig. 14 by spreading, suchas shown in Fig. 12. The same pattern is shown in Fig. 15, modulated asin Fig. 14, by spreading, and in addition, the tops are cut down forproducing an additional harmonic. In Fig. 16, the pattern shown in Fig.13, having, for example, 1000 cycles, is synthesized by spreading, asshown in Fig. 14, to create an additional 200 cycle harmonic,synthesized with a 500 cycle harmonic, produced by cutting down thetops, and also synthesized with a harmonic of 800 cycles which isproduced by cutting the bottoms. All harmonics are synthesized atpredetermined intensities which are fractions of the full amplituderepresented by thewldth of the wave patterns, as shown in Fig. 13.

Thus, the wave forms which modulate the light energy by cam action canalso be modulated ad ditionally, in three ways; first, by distortion ofthe wave patterns, second, by stretching, and third, by cutting the topsand bottoms in any predetermined periodic cycles. This is provided inorder to produce additional synthesis of harmonies with fixed waveforms, which sometimes can be accomplished by additional alteration ofalready drawn waves. This system is capable of producing numerouscombinations and alterations, and I donot wish to be limited to thosefew which have been illustrated.

Fig. 1'7 illustrates one and two side modulation. The one sidemodulation produces very small angles, and thus, very sharp peaks as canbe seen by. the angle a which has a measurement of eight and one halfdegrees, the wave pattern representing a frequency of, for example, 4000cycles, while the two side recording, at 4000 cycles, produces an angleof 17 degrees as seen in b. Therefore, it can be seen that the two siderecording is more accurate, and in photographing, it permits 'greatersharpness. When there is limited space for sound track patterns, Iprefer to use the two side modulation.

Fig. 18 illustrates the diiference between one side and two sidemodulation, as a and b respectively, when the wave pattern has manycharacteristics. It can be seen that much greater angles are obtained bytwo side modulation, providing more room for the peaks, permitting of.greater accuracy.

Fig. 19 represents mathematical synthesis of wave patterns on a drawnwhich is drawn on a ruled surface as described, for producing a qualityfilm. It can be seen that the wave 59 can be used for low frequencies,rather thanfor high. Sincethe wave is larger than the width of thescanning slit, the peaks can be easily photographed for use in covering,for example, the first two and one half octaves. However, for higherfrequencies, the wave length becomes more condensed. which calls forsimplification of the wave form. 50 represents the simplification ofwave 58 to cover, for example, from the first two and one half octavesto the fifth octave. 8| represents the simplified wave for covering, forexample, octave, and 82 represents the simplified wave 59 to cover forexample, the sixth to the seventh octave. This simplification isaccomplished by graph, the result of j the fifth to the sixth choosingcorrect intensities of the constituent harmonics.

This musical'system also provides that several tones can be producedfrom one wave pattern.

For example, by the pressure of one key, a chord can be produced, forobtaining predetermined tone qualities. The effect is similar to that ofa conventional pipe organ, on which a chord is sustained with varioustones, by the pressure of several manuals. The advantage of my inventionis that the quality is predetermined and obtained from -a single qualitypattern. Regarding my methods of synthesis I would call attention to mypatent, Number 1,948,169, dated February 20, 1934; my co-pending patentapplication filed February 11, 1930, Serial Number 427,628, and allowed;my application filed June the first two and one half octaves to thefourth.

octave, c, c, andc cover approximately from the fourth octave to thefifth and one half octave, and d, d and d" cover approximately from thefifthand onehalf octave to the seventh octave, and so forth. Besidethis-simplification modulation, changes in wave form' also come about bychanges in frequency, due to the difference in wave lengths.

Fig. 23. illustrates one unit of a commercial assembly, which includeskeyboard, pedals, motors, etc., as represented in Figs. 1 and 3, theparts being recognized by referring to the descriptive matter pertainingto said figures. However, a slight change in adjustment is illustratedin Fig. 23, wherein 9' represents a pedal which is provided forinserting the variable translucency tremolo disc 8 in the path of light'passing into lense I. The manually operated knob 9 is equivalent to'thepedal 9 shown in Figs. 1 and 3, for the purpose of controlling the vrevolutions of'disc 8.

Fig. 24 is a view of a. complete electronic musical instrument housed ina cabinet, 16 of commercial design, comprising tvW: independentunitssuch as that shown in Fig. 23, each said unit having its own keyboard,and also a reproducing apparatus for additional musicaleflects andexpressions, as shown in Fig. 2. The variouscontrol levers, the volumeindicating means. the keyboards, pedals, etc., can be recognized bytheir numerals, which are the same as those given in previous andfollowing descriptions.

' Fig. 25 represents the wiring for .a musical instrument as shown inFig. 24, with the exception of the reproducing apparatus, a and 1)represent individual units as shown in Fig. 23, whose light sensitiveelements, which may be single or a plurality connected in series, andpre-amplifiers have connection to a mixer, as shown.. The

additional gain and power amplifier feeds the speakers 63, 64, and 65,which have various frequency ranges, and are housed inside the cabinet.l6 of the instrument and also placed at any distance. For the purposeof silent practice,

so that others cannot hear the output, the operator is provided with ahead-phone attachment as 66, see my patent of August 29, 1933, Number1,924,713. 7

For the purpose of utilizing the amplification system of the instrumentfor announcing, the public address system microphone 61 is provided.

'Also, if it and line I1 is desired to reproduce recorded electricalmusic, the phonograph pickup 68 with line 18 is connected as shown.These various selective connections make the instru-- ment a universalone.

In Fig. 26, the units a and b are shown with their light sensitiveelements,pre-amplifiers, and mixers as in Fig. 25. However, in addition,the unit a is shown, provided for utilizing the reproducing device asshown in'Fig. 2. All of the preamplifiers are shown connected to acentralizedmixer to be transmitted over 69 to distant gain and poweramplifiers and from thence to feed speakers as in Fig. 25.

66' and 61' are provided for silent practice" and speech and singingamplification, respectively. The AC line' 10 supplies a rectifier withcurrent to feed the light sources as It, and the pre-ampliflers of unitsa and b. Fig. 26 illustrates the wiring of a complete AC operatedmusical instrumentwith the expressional reproducing device as shown inFig. 2.

Fig. 27 represents the combination wiring of a type used in an orchestrawhich is composed of a plurality of my electronic musical instruments.0, a, a",etc., are units as a and b of Figs. 25 and 26, with head-phoneconnections 66" and microphone connections 61", which are connected tothe mixer of each unit.' A conductor of the orchestra controls all ofthe individual units by means of the centralized mixer II, and,

in order to visualize the output of each unit as well as the intensityof the combined outputs of all the units, he switches on and 01!, atdesired intervals, the oscillograph 12.

Current from the mixer is transmitted to additional gain and poweramplifiers. Each of said amplifiers feeds its own individual banks ofspeakers of different frequency. ranges as T3 and I4.

invention, what I ing units comprising an individual standard keyboard,a bank of'shutters, each: of. said shutters in said bank beingindividually connected tq its.

own co-operative key in said keyboard, a set I diminishing rollersfor'supporting and individii ally closing each of said shutters in saidbank, automatic means for individually closing said shutters, a pedaloperated speed control for varying the revolutions of all diminishingrollers in said set, means for connecting and disconnecting thediminishing means, a light source, a stationary single aperture lightlimiting mask in the 'ting system, each of said electrical tone generatafront of said light source, a single optical system for the projection.of light of said light source front of said photoelectric element, auniformly repeating light scanning pitch means operating in conjunctionwith said optical system, a synchronous motor for driving said scanningpitch means and maintaining international pitch, means for varying thespeed of said scanning pitch means, for flattening and sharping theinternational musical pitch, a stationary preadjustable quality beltmask for selectively and individually modulating the intensity of saidpredetermined pulsating light energies which are i produced bysaidscanning and projectingpitch means, said quality belt mask comprising aplu-.

rality of different specially and synthetically prepared sections, eachof said sections having a predetermined number of vertical rows oftranslucent patterns and apertures of predetermined shapes and sizes,manual means for preadjusting any of said different sections in saidquality mask in register with said scanning pitch means, swell pedalmeans, tremolo pedal means for controlling the increase and decrease ininte'nsity in predetermined selective beats, per predetermined fractionof time, in said light energy, means for indicating and registering theamount of light energy impressed on said photoelectric element, saidelectrical tone reproducing unit comprising a'keyboard, a bank ofshutters, each of said shutters in said bank being individuallyconnected to its own co-operative key in said key-.

ture light limiting mask in the front of said light source, a singleoptical system for the projection of the light of said light source. invariable amounts onto a photoelectric element, a photoelectric element,a stationary light limiting single aperture mask in front of saidphotoelectric element, a multi-track belt record, with a plurality ofparallel tracks recorded and synthetically prepared, each of said tracksrepresenting a record of predetermined musical tones of predeterminedquality and pitch, each of said tracks predeterminedly co-operating withits own key in said keyboard in conjunction with said single opticalsystem, which is common to all tracks, a synchronous motor for drivingsaid multi-track record at a uniform speed for perfect tuning with saidelectrical tone producing units and for maintaining international pitchof the musical tones, means for selectively changing the speed of driveof said multi-track record for playing said record in different musicalkeys, swell pedal means, tremolo pedal means for controlling theincrease and decrease in intensity of predetermined selective beats perpredetermined fraction of time in said predetermined light energy, and acommon amplifying and sound emitting system for said electrical toneproducing units and said electrical ton-e reproducing unit.

2. In combination, an electric musical system comprising a console, aplurality of electrical tone generating units, an electrical tonereproducing unit; a transcription table with a phonograph pick-up, amicrophone pick-up, a headphone attachment, and a common-for-allamplifying and sound emitting monitor and distant system, said tonereproducing unit and each of said tone producing units comprisingindependent identical means, as, an individual keyboard,

a bank of shutters, each of said shutters being individually connectedto its own co-operative key in said' keyboard,"'a set of diminishingrollers for said bank of shutters, for individually supporting andautomatically closing each of said shutters at a predetermined fractionof time.

means for connecting and disconnecting the action of said diminishingmeans, a motor for driving said set of diminishing rollers, a pedaloperated speed control for varying the revolutions of all saiddiminishing rollers, a light source,

a stationary single aperture light limiting mask, in front of said lightsource, asingle optical system for projecting the light of said lightsource in variable amounts onto a photoelectric element, a photoelectricelement, a stationary light limiting single aperture mask in front ofsaid photoelectric Qement, a uniformly repeating scanning meansoperating in conjunction with said optical system for the projection andpro-' duction of a predetermined number of pulsating light energies fromsaid light-source, a synchronous-motor for driving said scanning meansand for maintaining precisely international musical pitch, means foradjusting the speed of said scanning means, tremolo pedal means forcontrolling the increase and decrease in intensity of predeterminedselective beats in said predetermined amounts of light energy beforesaid light has been impressed on said photoelectric element,

swell pedal means for controlling the intensity of the predeterminedlight energy before said lightenergy is impressed on photoelectriceleferent sections in said quality mask in register with said scanningmeans, a motor driven turn table-with a phonograph record electricalpick up coupled into a common amplification system and a sound emittingsystem of said electric musical system, a common amplification systemcomprising a plurality of individual preamplifiers and a common poweramplifier, a microphone pick-up coupled with said common amplificationand sound emitting system of said electric musical system, a head-phoneattachment for silent practice,a plurality of monitor loudspeakers and aplurality of loudspeakers at a predetermined distance.

3. A multi-manual console tone "producing and tone reproducing electricorgan'with an electrical phonograph attachment for self-playing and asound amplifying microphone pick-up, both working through a commonamplifying and sound emitting system, said organ comprising a sectionalbelt mask with'parallel multi-tracks, each section of said belt maskhaving a predetermined number of'sound tracks for producing tones ofdifferent predetermined pitches and the same quality, said sound tracksof eachsection being recorded and synthetically prepared, each saidtrack representing the predetermined pitch of a musical tone and alwaysbeing in the same predetermined location in all sections of said-beltmask, uniform repeated patterns of predetermined linear dimensions,usually termed as wave length, in each predetermined sound track of saidbelt mask being synthetically prepared in linear scale in proportion tothe frequency of the musical tone which said sound track produces,uniformly repeating patterns in each sound track of a predeterminedsection of said belt mask, of predetermined shape, usually 0 termed aswave form, being synthetically prepared in designfor predeterminedquality of the musical tone which said sound track produces,

each said sound track continuing through all sections withoutmismatching, and being made to produce tones of the same pitch in allsections of said belt mask.

4. ma multi-manual electric organ, a console having a plurality ofindependent electrical tone generating units and one electrical tonerepro- 2o ducing-unlt, all coupled to a common amplifier and commonsound emitting system, each 01 said units comprising a keyboard, a bankof shut-' ters, an automatic tone diminisher, a light source,

a single optical system, a synchronous motor, means. for producingindependently a plurality of tones at predetermined pitch andpredetermined quality, a" swell pedal means, tremolo means, and aphotoelectric element with electrical connections to said commonamplifying and 80 sound emitting system.

5. A multi-manual console electronic organ housing one and moreindependent electrical tone generating units, a common amplificationsystem, a common sound emitting system, an external phonographself-playing attachment, and

a sound amplifying microphone pick-up, comprising a plurality ofsynthetically made belt masks, one i'oreach said tone generating unit,each said belt mask being assembled irom a plu- 40 rality of differentsynthetically prepared and recorded belt sections of predeterminedlength, each of said belt mask sections bearing a plurality of parallelsound tracks, each said sound track in each said belt mask section beingassembled into one row 01' sound tracks without mismatching, each ofsaid matched sound tracks through all of said sections beingsynthetically made to produce only one predetermined pitch.

of musical tone, each of said matched sound tracks of all said beltsections being made to produce tones of the same pitch and differentpredetermined qualities, one in each of said (111- generating units, amicrophone pick-up, an elec- 05 trical phonograph and electricalphonograph pick-up, and a common-,to-all amplification and soundemitting syste;

v 6. In a multi-manu electric organ with individual tone generating andtone reproducing 70 units, asynchronous motorfor each of said units,

, for maintaining precisely the international musical pitch of saidorgan in all of its manuals, said synchronous motors'operating on thecycles of an alternating electric current supply, with- 75 out changingtheir speed from voltage variation operated by each of said keys,'adiminishing at- 10 tachment, a light source, a stationary preadjustablequality belt mask, a moving scanning belt mask, a synchronous motor, vasingle optical system for projecting said light energy through saidstationary and moving belt masks in predeter- 15 mined register onto aphotoelectric element for conversion of said light energy into soundenergy.

8. In a multi-manual electric organ, a plurality of tone generatingunits, each havingz-a keyboard, a set of shutters, a light source, aquality belt mask, means for presetting said mask, a rotary scanningelement, asynchronous motor for driving said scanning element, a commonoptical system for projecting and moving in one direction aillament oithe said light source, by 2! said rotary scanning means, on apredetermined area of the said' quality belt mask, means for producing apreadjustable beat tremolo, and means for metering the output of each ofthe said tone generating units; 80

9. In a multi-keyboard electronic organ, a keyboard operated electricaltone reproducing unit,

a keyboard, .a bank of shutters, a diminisher, a single filament sourceof light, a stationary light gauging mask, a single optical system forprojecting the said filament of light source across one and more soundtracks of the quality mask,

a multi-track quality mask with sound tracks of predetermined pitchesand predetermined qualities, a synchronous motor drive, a musical key tochanging meansfor said synchronous motor drive,

a single photo-electric element, a variable beat tremolo attachment, anda graduated volume control.

10. In an electrical musical instrument in which musical tones ofpredetermined quality and pitches are produced, a keyboard, a set ofshutters, each shutter connected to its own cooperative key in saidkeyboard, a diminishing attachment for automatically closing themanually opened individual shutters of the keys oi said keyboard, meansfor predeterminedly presetting a rate of time for diminishing theelectrically produced tones, and means for connecting and disconnectingsaid diminishing means.

11. In a multi-manual electrical musical instrument in which musicaltones are produced and reproduced photo-electrically in conjunction withmulti-track sound records and the action of keyboards; light sources,photo-electric elements, synthetically prepared stationary and movingtrack record masks, keyboards with sets of shutters, one 01 saidshutters for each sound track, and a single common optical system foreach of the tone producing and reproducing units, for 55 thesimultaneous selectiveprojection and scanning by said light source, oneand more sound tracks of the said stationary and moving multitrack mask.

l2. Aphoto-electrical'organ, comprising, akeyboard, a set of shutters, adiminisher, a single filament light source, a single common lens forprojecting and focusing on 'a multi-track belt record predeterminedportions of said single filament of said light source, when selectedshutters have been opened by theaction of their cooperative keys of saidkeyboard, a multi-sound track belt record of predetermined length with aplurality of parallel sound tracks of periodic Wave patterns of recordedand synthetically prepared sound, each of the said sound tracks beingmade to produce one predetermined pitch and predetermined quality ofsound, a synchronous motor with a drive for moving in a predeterminedselected direction at a constant uniform speed, the said multi-tracksound record, and a multi-track belt drive with a speed changer forpredeterminedly and simultaneously varying the the key in all of thesaid multi-tracks of said belt record.

13. A photo-electric organ comprising; means for keying and opticallyscanning by light a mov: ing multi-track record, a multi-sound trackbelt record with sound tracks, each track having a predetermined pitchof sound and a non-periodic predetermined quality of sound, and asynchronous motor drive with a speed changer for the,

simultaneous and selective playing of all of the said sound multi-tracksat a predetermined dif ferent musical key. I

14. A method for tuning and keeping in tune at a predeterminedinternational musical pitch, one and more 'predeterminedly designedelectromechanical units, each of which is made for generatingindividually one and more predetermined musical ton'es electrically,said units operating from a commercial source of alternating electriccurrent power supply of predetermined fixed frequency and variablevoltage, by driving each of the said independent electro-mechanic'altone generating units, with the aid of a synchronous motor ofpredetermined speed and cycles, said synchronous motor being subject tovariation in speed only from the variation of the cycles and not fromthe fluctuation of the voltage of the A. 0. current on which the saidmotor isoperating. v

15. A method for generating electrically a plurality of musical tones atconstant uniform pitches in perfect tune with the standard internationalmusical pitch, using a standard commercial source of electrical energyof a fixed number of cycles and a fluctuating voltage for driving theelectrical tone generators, by driving said electrical tone generatorsusing an electric motor ducing musical tones photoelectrically, akeyboard with a set of light shutters, a light sourcewith a singlefilament of a predetermined dimension, a preadjustable stationary beltmask with a predetermined number of rows of apertures of predeterminedsize and shape, a synchronous motor for uniformly rotating in apredetermined direction a multi-sided pitch scanner for reflecting andsuccessively projecting a predetermined portion of the image of thelighted filament of said light source when predetermined shutters havebeen opened by the action of their co-operative keys in said keyboard,through predetermined apertures of said belt mask into a photoelectricelement.

17. In a multi-manual electronic organ indlvidual tone generating units,a plurality of keyboards, a plurality of shutters, light sources,stationary and moving belt masks with rows of apertures for modulatingthe light passing through them, a plurality of optical systems forfocusing and projecting the images of said light sources through theapertures of said belt masks, synchronous motor drives for moving saidbelt masks, preadjustable beat vibrato means for each of said tonegenerating units, and means for controlling the volume of sound fromeach of said tone generating units.

18. In a machine of the class described, the combination of a set ofshutters, a light source, on automatic diminisher, a keyboard, anoptical slit multi-scanning means, a lens, a preadjustable quality beltmask, a photoelectric element, and a I galvanometer' metering means,including said common light source, an optical system, a galvanometer, arotary disc with predetermined rows of perforations, a photoelectricelement, and amplifying and registering means, said metering meansoperating in synchronism with said scan ning means, for measuring andindicating the intensities of the output of said machine under differentpredetermined conditions.

19. In a muitimanual photoelectric organ, light sources which arecontrollable by the action of keyboards, optical scanning means, aplurality of synthetic sound-on-film moving and stationary belt masks,and photomechanical means for the synthetic preparation of said movingand stationary belt masks, said masks bearing a plurality of soundtracks of different predetermined pitches, volumes, and qualities.

20. In a multi-manual photoelectric musical instrument, a plurality oflight sources, a plurality of optical systems, a plurality of opticallight scanning means, synchronous motor drives, a plurality ofpreadjustable sectional belt masking means, the predetermined sectionsof which are predeterminedly scanned by said light scanning means, eachsection of said belt. mask being manually, synthetically, andphotomechanically prepared, for the production of tonesphotoelectrically, said tones having predetermined pitches, qualities,and volumes, in conjunction with light sources, scanning means, and aphotoelectric element.

21. In a multi-manual photoelectric organ, a plurality of moving andstationary belt masks, each bearing m'ulti-track sound records inparallel rows, said belt masks being predeterminedly and syntheticallyprepared by manual delineations, and photo-mechanically with a flatfield corrected optical system recording means, for the production ofpredetermined sounds of predetermined pitches, volume, and syntheticqualities,

. the complex wave patterns used in the production more movingpredeterminedly recorded and synthetically prepared multi-tracksound-on-iilm endless belt mask records of predetermined length, for theproduction of sounds of different predetermined pitches of a musicalscale, different predetermined qualities, and different predeterminedvolumes, said multi-tracks of said belt mask records beingpredeterminedly recorded for predetermined fixed pitches, andpredetermined fixed qualities, predeterminedly recorded forpredetermined fixed pitches and non-periodic qualities, andpredete'rminedly recorded for non-periodic pitches and nonperiodicqualities, a synchronous motor drive with a speed changer of fixed stepsfor driving said multi-track belt mask records, a flat field opticalsystem for simultaneously projecting and scanning all of saidmulti-tracks. a light source, a keyboard with flexibly connectedshutters, and a common amplification and sound emitting system.

23. In a photoelectric musical instrument, a multi-sound-trackcontinuously running belt record, which has been predeterminedlyrecorded and synthetically prepared, a key-operated shutter for each ofsaid sound tracks, a keyboard, a light source, one optical system forscanning all of said tracks'simultaneously, a photo-electric element, asynchronous motor drive with a gear box and a predetermined speedchanger, an automatic diminisher with a variable diminisher timecontrol, an automatic vibrato with variable beat volume control, anelectrical phonograph pick-up, a microphone pick-up, a mixer, and acommon amplifying and sound emitting system.

24. A multi-manual photoelectric organ, comprising a plurality ofkeyboards, with standard hollow'metal keys, and a typewriter typekeyboard, each key of said keyboards being connected to its co-operativeindividual light shutter, a plurality of sets of light shutters, aplurality of automatic motor driven diminishers with off and onconnecting means for each individual diminisher, aplurality ofstationary and moving multitrack quality masks, a light source for eachof said quality masks, a flat field corrected lens for each lightsource, a monitor set of speakers, an echo organ set of speakers, and acomplete electrical phonograph, and phono-pick-up monitor and distantmicrophone, switched on and off from the console of said multi-manualorgan.

25. A photoelectric musical instrument .com-

prising a plurality of endless belt masks bearing a plurality of soundtracks synthetically and predeterminedly recorded for the production ofsound photoelectrically, said sound having predetermined pitches,qualities, and volumes, a plurality of light shutters, one light shutterbeing provided for each of said sound tracks, a plurality of keysco-operating with their own light shutters, an optical system for eachof said endless belt masks, a light source, automatic diminishing means,a synchronous mot-or drive for moving said belt masks, a photoelectricelement for each of said belt masks, and a common amplification andsound emitting system for said plurality of belt masks.

26. A photoelectric musical instrument com prising one and moreelectrical tone generating units, each said unit comprising a lightsource, a set of shutters, a set of keys for opening and closing saidshutters, an endless moving pitch belt mask, a stationary quality beltmask, a fiat field corrected optical system, a synchronous motor with abrake for predeterminedly varying its speed, a photoelectric element,for each of said tone generating units, a set of monitor speakers, a setof distant speakers for producing echo effects, a microphone, asynchronous motor driven phonograph turn table with an electricalphonograph pick-up, and a common-for-all amplification sys- I tem.

2'7. In an electric organ, a keyboard, a set of shutters cooperatingwith the keys ofsaid keyboard, a diminisher, a light source, an opticalsystem, volume controlling means, tremolo producing means, a multi-soundtrack moving record, each individual sound track of said record havingpredetermined pitch, quality, and volume, and having been recorded inpredetermined tune and according to the predetermined law of volumedistribution throughout its musical range, and a constant speed motorfor driving the said multitrack belt at a predetermined uniform speed.

IVAN EREMEEFF.

